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the surface of contact of sphere and fluid on the magnesian limestones of the Ozark being conducting, currents will be incited Series, and then out toward the east, at the in the fluid that will pass into the sphere expense of the lower members, each stratum and out again.
overlapping that which is under it. In the In the case of the earth there is no fluid vicinity of the limestone breccia they prewith reference to which the solid earth per- sent the following sections: 1. Green Shale, forms a total differential rotation ; still 7 feet. 2. Shaley Limestone, 10 feet. 3. there are partial differential rotations due Speckled Crinoidal Limestone, 3 feet. 4. to moving streams, ocean currents, tidal Basal Conglomeratic Sandstone, 4 inches. waves and air currents. Such a field, if it Proceeding south along the west side of exist, can be differentiated with the aid of the valley we find the first indication of the potential theory.
a disturbance in the form of a gentle unduPurely local disturbances would consti- lation of the upper portion of the shaley tute a fourth—the 'anomalous field.'
limestone, No. 2 of the section. A few We as yet have no satisfactory answer as hundred yards further we encounter the to the origin of the earth's primary mag first of a series of huge masses of breccia, netic field, neither has the astronomer an consisting of the light gray, amorphous answer to the query Whence the moon.' limestone and thin shale of No. 2, broken He, however, accepts the moon's existence into angular fragments of various sizes, and and computes its disturbing effects upon recemented, partly by a similar substance, the earth's motions. Just so it is with the and partly by the subsequent infiltration of earth's magnetism. We do not know calcareous matter occurring now in the form whence it has come, but we know it is of calcite. The original bedding planes there. We know that to-day the mag- have been mostly obliterated, and the brecnetic earth is rotating about an eccentric cia weathers out along the hillside in boulaxis, and so let us ask ourselves What der-like masses, 10 to 20 feet thick, and 50 is the effect of the self-inductive action of the to 100 feet in width. A stratum of shaley rotating magnetic earth ? How is the prin- limestone at the base of these masses participle of the conservation of energy when applied ally retains its original appearance, and to the motions of the magnetic earth to be ful- from its relation to the more massive brecfilled ?
L. A. BAUER. cia overlying it the whole is seen to have
been subjected to violent contortion and ON A DEVONIAN LIMESTONE-BRECCIA IN fracture, such that boulders of hard limeSOUTHWESTERN MISSOURI.
stone have been forced into the midst of The brecciated limestone which it is pro- calcareous shale. There are about half a posed to describe in this paper outcrops dozen of these masses exposed along the valnear the base of Eagle Ridge, on the west ley side, in a distance of about 1000 feet; side of the valley of Dry Creek, five miles then the undulations decrease, and at onewest of the town of Galena, county seat of half mile from where the first disturbance Stone County, Missouri. The several mem- in the strata was noticed they entirely bers of the Devonian strata in this portion cease, and from thence down the valley the of the State are, in their normal condition, strata are in their normal condition. very regular and evenly bedded, and are There is no indication of the action of perfectly conformable, from their base, to water in the formation of the breccia. All and with the overlying Kinderhook Group. the fragments are sharply angular, and freThey rest, with slight local unconformity, quently a fossil has been broken through and the positions of the pieces slightly discovered, that they suddenly gave way, changed, but not widely separated as they were contorted, brecciated, forced forward would inevitably have been had the brec- and hurled in boulder-like masses on to other ciated masses been accumulated by wave undisturbed strata. action on a seashore. The hypothesis that Considering the intensity of the force and the brecciation and contortion were pro- the conditions under which it was applied, duced by undermining of the strata and by it is surprising that the area of the disturbsubsequent crushing from the weight of the ance should be so small; on the opposite superincumbent rock is inconsistent with side of the valley, one-eighth of a mile disthe facts. The lower members of the De- tant, there is not the slightest sign of it, and vonian strata are undisturbed, and in the in the next valley, one-fourth of a mile southcentral portion even the whole of No. 2 west from it, the Devonian strata are undisseems to be present and perfectly horizon- turbed. Its areal extent cannot be greater tal and the breccia rests on it increasing than one-fourth square mile. the thickness of the Devonian strata from The lithification of the shaley limestone its normal 20 feet to 40 feet in the central was practically complete at the time of the portion of the disturbance.
displacement, for the fragments are all In short, the only theory which will ex- sharply angular and must then have been plain all the phenomena is that which has very hard. And as the relation of the overbeen applied, in explanation of the manner lying strata shows that the period of the of formation of similar but vastly more disturbance immediately succeeded that of extended Devonian limestone breccias in deposition of No. 2, deposition and lithificaIowa, viz., by lateral pressure produced by tion must have proceeded contemporanethe 'creep' or sliding on a sloping sea bot- ously. tom of the displaced strata immediately The green shale, which is the upper memafter their deposition.
ber of the Devonian in this region, thins From a study of the strike of the undu- out in the hollows between the dome-shaped lations, displacements and other attendant prominences of the surface of the breccia, phenomena, it becomes evident that the and totally disappears over the higher porpressure was applied from the northeast. tions of the disturbed area. The points The Devonian strata at present rise in that where it is absent are not now and never direction at a rate not exceeding 8 or 10 were more than twenty feet higher than the feet per mile, and during the Devonian age surrounding sea bottom, where the green were doubtless still more nearly horizon- shale was deposited in very regular lamital. It is remarkable that so slight a slope næ, without wave action. The areal discould have given rise to a sliding of a por- tribution of the green shale is such as to tion of the sea bottom, but it is undoubtedly show that it was deposited in a comparathe fact that, while the deposition of the De- tively small and shallow esturine basin, vonian strata had proceeded without in- connecting with the sea toward the south, terruption to the top of the shaley limestone and supplied with fine sediment from the No. 2, the upper 2 or 3 feet began to slide on land on the east and north. The limited the underlying stratum. About the western extent of this body of water accounts for line of Stone county the resistance over- the feebleness of its waves, which did not came the weight of the creeping strata, affect the green shale at the depth of only and the tension becoming too strong, at one twenty feet around the elevated area formed place certainly and perhaps at others not yet by the breccia. The higher prominences of the breccia were slightly eroded by wave origin of certain cloud forms, and much action during the deposition of the green difference of opinion still prevails on the shale in the surrounding water, but the subject. Four chief classes are recognized leveling had not proceeded far when the in Ley's scheme: clouds of radiation, such Devonian age came to a close ; the entire as ground fogs; of inversion, such as cumregion was depressed, and the Louisiana ulus, dependent on overturnings in an unlimestone (formerly known as the Litho- stable atmosphere; of interfret, such as graphic limestone), or basal member of the waving stratiform clouds formed at the conKinderhook Group, was laid down over the tact of layers of different temperature ; and breccia. It is usually a regularly bedded, of inclination, such as pendent cirrus wisps, dark gray limestone, everywhere perfectly caused by the settlement of particles from conformable to the green shale, but over one atmospheric stratum into another. The the distributed area it is irregularly bedded illustrations, reproduced from photographs and slightly arched, but soon succeeded, by by Clayden, are for the most part excellent. thickening in the hollows and thinning over The chief deficiency of the work is the abthe prominences, in leveling off the ancient sence of comparative tables, by which the sea bottom. The Lower Carboniferous terms proposed by Ley may be translated strata are here locally unconformable with into those adopted by the International the Devonian. We have thus seen that the Meteorological Congress. In a number of thinning of the green shale over the area of passages exceptions must be taken to the disturbance fixes the time of said disturb- manner of physical explanation of cloud ance at the period between the deposition formation, especially to statements concernof Nos. 1 and 2 or the shaley limestone and ing the relation of water and ice particles the green shale. From a general resem- in cumulus and cirrus clouds, and to the reblance between the shaley limestone of this peated implication that the liberation of laregion and portions of the Cedar valley tent heat in the condensation of vapor aclimestone of Iowa, and from the fact that tually warms the air. The chapters on the this peculiar mode of brecciation obtained theory of atmospheric currents and on the in both regions, I wish to suggest that the prevailing winds of the globe are hardly light brown or gray, amorphous, shaley relevant to the rest of the book and add limestone of southwestern Missouri may be little value to it. Remembering that the the equivalent of the Cedar valley lime- author has devoted years of observation to stone of central Iowa.
cloud study, and that latterly his work has OSCAR H. HERSHEY. been much interrupted by ill health, it is GALENA, Mo.
doubly a regret that his book cannot be
more highly commended. CURRENT NOTES ON PHYSIOGRAPHY (18.) LEY'S CLOUDLAND.
BUREAU CENTRAL MÉTÉOROLOGIQUE. This long expected work (Stanford, Lon- The latest series of Annales of this imdon, 1894. 208 p.) is an effort to establish portant Bureau contain as usual a volume a classification and terminology of clouds of memoirs in which, besides the statistical on a genetic basis. While such a plan has studies of thunder storms in France by Fron much to commend it, and must eventually and several reports of magnetism, there are be adopted in fully developed form, its essays by Angot on the advance of vegetapresentation now is perhaps premature; for tion and the migration of birds in France there is yet much to learn regarding the for ten years, 1881-1890, and on the meteorological observations on the Eiffel tower parent periodicity, Köppen remarks that during 1892; and by Durand-Gréville on thus far all efforts to establish weekly, squalls and thunderstorms. Nearly all the monthly or longer weather cycles have, features of the advance of vegetation exhibit without exception, failed, and that, while the accelerating influence of the Mediter- the faint and easily obliterated traces of ranean and the retarding influence of the such periods have a certain scientific inBay of Biscay. The records of the Eiffel terest, they have not yet a practical value. tower are chiefly interesting in showing in- The Annalen der Hydrographie is a characterversions of nocturnal temperature in the istic German journal, in which a serious means of all the months, and consequently and scientific style of work is carried into in proving a distinct variation in the diurnal the accounts of foreign coasts and harbors, values of the vertical temperature gradient as reported by officers of the marine. It in the lower atmosphere; as well as a change frequently contains articles and reviews of of the time of maximum wind velocity from interest on winds, tides and currents. afternoon at surface stations to night at the top of the tower. Durand-Gréville's essay
ELEVATION AS A CAUSE OF GLACIATION. is illustrated by an excellent chart of the It is probable that no one questions the distribution of pressure during an extended sufficiency of elevation to account for glasquall that occurred on August 27, 1890; ciation, if other things, such as external the isobars being drawn for every milli- controls of climate, remain unchanged; but meter, and showing a sharp N-like double there are serious difficulties in the way
of bend at the place of the squall.
accepting the thesis maintained by Upham (latest expressed in Bull. Geol. Soc. Amer.,
vi., 1895, 343–352) to the effect that THE famous Christmas storm of 1821, the glacial sheets of northeastern America which led Brandes and Dove to their and northwestern Europe were caused by early statements concerning the system of and hence were coincident in time with the storm winds, finds a modern parallel in a elevation that permitted the erosion of the storm of December 22-23, 1894, described deep marginal valleys of the continents. by Köppen in the Annalen der Hydrographie, Upham cites the case of the Sogne fiord, on edited by the Naval Observatory at Ham- the west coast of Norway with a maximum burg, and published in Berlin. On the morn- sounding of 4,080 feet, as a measure of the ing of December 22 the storm center, with a epirogenic uplift which at its culmination pressure of 715 mm., lay just east of Scot- caused the glaciation of northern Europe. land; on the evening, with a pressure of The difficulty here is that while a compara725, the center lay just west of Denmark. tively long period of elevation must be posThe whirling courses of the winds are well tulated for the excavation of the valley of illustrated ; a southerly gale crossed the Sogne fiord, and while climatic change Baltic, while a northerly gale raged on the would respond immediately to elevation, North sea; violent east winds blew off the yet glacial conditions are not known to coast of Norway, and westerly gales were have occured until the erosive effects of recorded in northern Germany. Disastrous elevation were practically completed. The storm floods were felt at many points on steepness of the fiord walls indicates that the coast, and salty rain fell at many points the elevation was not slowly progressive, in England. Other storms were felt a week but was rather promptly completed and earlier and later ; but, apropos of this ap- steadily maintained; being in this unlike
WINTER STORMS IN THE NORTH SEA.
FORESTS AND TORRENTS.
the elevation by which the erosion of the ogy, Meteorology, Soils, Fertilizers, Field flaring and benched valleys of the northern crops, Horticulture, Forestry, Seeds, Weeds, Alps has been allowed. The problem in- Diseases of Plants, Entomology, Foods, volved in the relation of elevation and gla- Veterinary Science, Dairying Technolciation would therefore seem to be not the ogy, Statistics and Miscellaneous, the progsimple one of immediate cause and effect, ress made in these various branches in the but on the other hand the difficult one of Experiment Stations of our country. The why the apparently competent cause should recent work in Agricultural Science in fornot have at once had its expected effect; eign countries is also briefly summarized. why glaciation should have waited so long From the last issue of the Record, just after elevation, not attaining its maximum received, the reader is first of all informed until a time of depression.
as to the amounts of the appropriations made by Congress for the U.S. Department
of Agriculture for the year ending June 30, The much-debated problem of the influ
1896. The total amount is $2,578,750, ence of forests on rainfall remains unproved, which includes $720,000 for the Experiafter all that has been said and done; but
ment Stations established under the act of the influence of forests on torrents admits Congress of March 2, 1887. There will be of no question. The soil is washed from
two new divisions in the U. S. Division the deforested slopes and the torrents spread of Agriculture, namely, that of Agrostology: it over the valleys, greatly to the injury of which contemplates ' field and laboratory both high and low land. The Shenandoah
investigation relating to the natural history, Valley, for example, one of the most beauti
geographical distribution and use of the ful and productive farming districts in our
various grasses and forage plants,' and that country, is suffering along its margin from
of Soils. the encroachments of gravels and sands washed from the enclosing deforested ridges. foreign lands is a paper upon · Agricultural
Among reports of agricultural science in Those who wish to present this matter to
Investigations in Switzerland,' by Dr. forestry meetings in popular and impres- Grete, director of the Swiss Station at Zusive form will find an abundance of illus
rich. In 1878 a Station for control of fertrative material with references to European
tilizers and feeding stuffs was established, literature on the subject in an essay by and recently its work has been extended to Toula: l'eber Wildbach-Verheerungen und die
include culture tests of soils. There is a Mittel ihnen vorzubeugen (Schr. Vereins zur
Seed Control Station which at the present Verbreitung naturw. Kenntnisse in Wien,
time has eight workers besides the director, xxxii., 1892, 499–622, with forty-one views
and tests by germination thousands of samfrom photographs). W. M. DAVIS.
ples of seeds. HARVARD UNIVERSITY.
Under the head of chemistry the Record
gives the new methods of obtaining solutions VOTES ON AGRICULTURE (III.)
in soil analyses and the determination of THE EXPERIMENT STATION RECORD. phosphoric acid. The department of Botany The Experiment Station Record, a contains a review of Professor Scribner's monthly (practically) published from the "Grasses of Tennessee, which is a valuable office of Experiment Stations of the C. S. contribution to the Agrostology of the whole Department of Agriculture gives under country. Notes on Maize,' by Dr. Sturtethe heads of Chemistry, Botany, Zool- vant, contains generalizations upon the